PROJECT SUMMARY The increasing use of electronic health records (EHRs) by cancer centers nationwide has led to the tremendous growth of repositories containing unstructured, free text notes. These notes include clinical concepts that cannot be found anywhere else in the EHR, and these concepts are needed to characterize a patient?s specific ?phenotype?. Having so much data available in electronic format provides unprecedented opportunities for advancing clinical and translational cancer research, yet many researchers do not have access to practical tools to assist with identifying and extracting the concepts from these notes. To address this problem, the University of Michigan Comprehensive Cancer Center Informatics Core developed the information retrieval tool EMERSE?electronic medical record search engine?which has achieved widespread local success in supporting hundreds of cancer studies and has led to over 120 peer-reviewed publications. EMERSE provides innovative features that enable research including visualization of results, reusable patient lists, and shareable sets of search terms (?Bundles?) that promote more reproducible searches. This project proposes to develop innovative capabilities within EMERSE and develop the infrastructure to widely disseminate EMERSE to cancer centers nationwide. The software innovations in this proposal include (1) securely networking the EMERSE instances to enable searches across cancer centers, which is important for rare cancers and is in alignment with growing national data sharing initiatives; (2) leveraging the networked EMERSE instances to share search knowledge between institutions in the form of stored search term Bundles, promoting the reproducibility of searches across sites as well as within studies; (3) supporting search with either fully identified or de-identified clinical notes, depending on the users? credentials and intended use, which is needed for cross-institutional searching; (4) supporting the inclusion of localized custom dictionaries or ontologies to be used for query expansion. The technical and collaborative infrastructure to support the widespread dissemination of EMERSE will be developed, including formation of the EMERSE Research Informatics Network (ERIN). Five cancer centers, each with varying health information technology environments, will join ERIN for this project and locally implement EMERSE, making it available to their researchers. Implementations will be staggered so that lessons learned from implementing at one site can be used to improve the documentation and be applied to future sites. Implementation details will include how to address regulatory, institutional review board, security, and compliance issues. The collective knowledge from these initial implementers will be integrated into a ?roadmap? guide to help future cancer centers and other institutions implement EMERSE with ease. EMERSE will be promoted to other cancer centers through various mechanisms. The impact and effectiveness of this work will be evaluated across multiple dimensions including information retrieval metrics, usability, implementation, adoption, satisfaction, and utility.